I live in Scottsdale, AZ and have HD cable from Cox. I've found that the major networks (NBC, ABC, CBS and Fox) have the best video during prime time and the live morning shows. That also holds true for most live events like golf, etc. Unfortunately, the video is always much better than the audio. I don't get a lot of content in anything other than stereo and sometimes it sounds better on the corresponding SD channel than HD.
The "cable channels" (TNT, Discover, Lifetime, etc.) that are also on HD seem to just be the SD with the picture stretched and re-broadcast. Again, the audio isn't terrific.
I used to think that my receiver was causing the audio problems but sometimes a TV program sounds great while others sound terrible and DVDs always sound good so it's the source (Cox). I've been tempted to switch to DirecTV but they want a 2 year commitment which seems like a long time if it doesn't solve the audio problem.
Joe
If you can't have fun doing it, it's probably not worth doing.